18-oxygenated steroids and process for their manufacture



United States Patent 3,014,029 IS-OXYGENATED STEROIDS AND PROCESS FOR THEIR MANUFACTURE Oskar Jeger, Zurich, Switzerland, assignor to Ciba Pharmaceutical Products Inc., Summit, NJ. 5 No Drawing. Filed June 16, 1959, Ser. No. 820,599 Claims priority, application Switzerland June 18, 1958 23 Claims. (Cl. 260-43955) The present invention relates to a process for the manufacture of new 18-oxygenated steroids.

'The invention relates more especially to a process wherein 18:ZO-cyclo-ZO-hydroxy-pregnane compounds are dehydrated and in the resulting A -pregnene compounds the l8:20-double bond is oxidatively split up. The process is illustrated by the following diagram of partial formulae:

3,014,029 Patented Dec. 19, 1961 of the species Ophiobolus herpotrichus or Sclerotinia fructicola and, when starting from the second compound, by reduction of the lactone group according to published methods. The products of the process may, however, be physiologically active themselves; thus, for example, the compounds corresponding to the last formula have an anabolic activity.

0 H2 v id oxidation U Depending on the oxidation agents used, the products of the process are either 18:20-dihydroxy-l8:20-cyclopregnane compounds or 18:20-dioxo-pregnane compounds 1 or 20-oxo-pregnane-18-acids. They have the following constitution in the rings C and D pounds, such as for example aldosterone. Of particular importance for the synthesis of aldosterone are the following two compounds OH 1 0H, CH3 OCH 1 0-o o The conversion of these compounds into aldo'sterone may be effected for instance by incubation with a fungus may be saturated in the ring system or contain double bonds, for example, in one or more of the positions 4, 5, 9 (11), 11, 14 or 16. By functionally converted hydroxyl or 0x0 groups respectively are meant esterified orctherified hydroxyl groups, or ketalized or enolized oxo groups, or oximes, hydrazones, semicarbazones.

A product of the present process that contains free hydroxyl and/0r 0x0 groups can be converted in the known manner into a functional derivative thereof, such as an ester, ether, enol ester, enol ether, acetal, a corresponding thio derivative (such as thio-ether, thio-acetal or ester of a thio-acid), or into a hydrarone or oxime thereof. The acid radical in the esters and enol esters are those of saturated or unsaturated aliphatic, cycloaliphatic, aromatic or heterocyclic monocarboxylic or dicarboxylic acids, preferably those having from 2 to' 8 carbon atoms or of sulfonic acid, or of phosphoric, sulfuric or hydrohalic acids. The radicals in the ethers, enol ethers, acetals or in the corresponding thioderivatives may belong to the aliphatic, aromatic or heterocyclic series; such radicals are, for example, lower alkyl or alkylene groups such as methyl, ethyl, propyl, ethylene, propylene groups or lower aralkyl groups such as benzyl-, diphenylor triphenyl-methyl groups, further tetrahydropyranyloxy groups or sugar radicals such as those of glucose, galactose or maltose.

For the conversion of the 18:20-cyclo-20-hydroxysteroids into lit-oxygenated steroids water is eliminated in the first reaction step. This is achieved by meansof a dehydrating agent such as thionyl chloride, phosphorus oxychloride, methanesulfonyl chloride or the like, in the presence of a substance of basic reaction such as pyridine, collidine or the like. Alternatively, water can be eliminated by treatment with a mixture of pyridine and bromacetamide or bromsuccinimide and subsequent treat- 0 ment with sulfur dioxide or by conversion'into ZO-O-acyl derivatives and by pyrolysis. 20-sulfonic acid ester groups (for example tosylates or mesylates) can' be elimiviolet spectrum: no bands.

nated by reaction with a solution of lithium chloride in dimethyl formamide. Water can also be eliminated with the aid of an acid silicate, such as fullers earth. The products resulting from the elimination of water are A l8:20-cyclopregnenes and A -18:20-cyclopregnenes.

The splitting up of the 18:20 double bond is carried out in the manner known for the oxidative cleavage of double bonds. The ozonides obtained by treatment with ozone are split by application of a reducing agent, such as zinc and acetic acid. Alternatively, the double bond can be hydroxylated, for example by reaction with a molar proportion of osmium tetroxide, the glycol thus formed being split up by means of per-iodic acid, lead tetraacetate or sodium bismuthatc. The double bond can also be split up by performing the oxidation with an alkali metal per-iodate, for example sodium per-iodate in the presence of a catalytic amount of osmium tetroxide with the addition of an alkali metal salt of a carboxylic acid such as potassium acetate, in an aqueous medium.

The following examples illustrate the invention:

Example 1 500 mg. of 3fl-acetoxy-20-hydroxy-18:20-cyclo-allopregnane are refluxed in a mixture of 10 cc. of acetanhydride and 10 cc. of glacial acetic acid for 1 hour, and the product, from which water now has been eliminated and which is unsaturated towards tetranitromethane (consisting of a mixture of A and A -18:20-cyclo-3B- acetoxy-allopregnene), is dissolved in 50 cc. of methylene chloride, and the solution at 40 C. is treated with an ozone current of 1% strength until a sample thereof no longer gives a color reaction with tetranitromethane. The solvent is then cautiously evaporated in vacuo at room temperature, the ozonide is dissolved in 50 cc. of absolute alcohol and subjected to reductive cleavage in the presence of 100 mg. of 10% paladium-calcium carbonate catalyst. On cautious oxidation with potassium permanganate, chromic acid or silver oxide the resulting 3fi-acetoxy- 18:20-dioxo-allopregnane yields the SB-acetoxy-ZO-oxoallopregnane-18-acid which can alternatively be prepared by subjecting the ozonide to direct oxidative cleavage with chromic acid in glacial acetic acid solution or with hydrogen peroxide in glacial acetic acid.

Example 2 itself for 5 hours at 0 C. The yellowish brown reaction solution is poured over ice and extracted with ether-I-meth- 'ylene chloride. times with 2 N-hydrochloric acid, three timm with ice- The organic layers are washed three cold'2 N-potassium carbonate solution and four times with water, to yield 585 mg. of a pale brown oil. Tetranitromethane test: positive. Infrared spectrum carbon tetrachloride: 1730 cm. and 1245 cm." (acetate), no hydroxyl band, no typical double bond bands. Chromatography of this oil on 19 grams of alumina and elution .with petroleum ether+benzene (2:1) gives in fractions 1-4 159 mg. of a colorless oil, all of which fractions turn yellow with tetranitromethane. The fractions 2 and 3 (151 mg.) crystallize after a short time and yield after two 'recrystallizations from hexane+methanol needles melting at 90-92 C. Beilstein test: negative. Ultra- On recrystallization from ethanol, A 18 20 cyclo 3,8 acetoxy allopregnene melts at 95 C.; optical rotation Fractions 7-10, eluted with benzene, yield 261 mg. of a spontaneously crystallizing compound. After recrystallization from methylene chloride-l-methanol crystals melting at 176-178 C. are obtained. Tetranitromethane test: negative. Infrared spectrum in carbon tetrachloride: 1730 cm." and 1245 cm.- (acetate); no hydroxyl band.

4 For analysis the product is recrystallized four times from methylene chloride+ethanol (M.P. 186 C.) and dried for 10 hours at C. in a high vacuum. C4GH7007S. Found: C 72.15%, H 9.10%; calculated: C 72.02, H

9.20. Optical rotation [a] =+5 (c.=0.631). The product is the ester 3 o-s-o AeO V OAc Example 3 The A 3e acetoxy 18:20 cyclo allopregnene obtained as described in Example 2 can also be prepared from 3 B-acetoxy-ZOE-hydroxy-l 8 :20-cyclo-allopregnane (300 mg.) by treatment with 4.5 grams of phosphorus oxychloride in the presence of 5 grams of pyridine for 2 hours on a water bath. After working up, 281 mg. of crude product are obtained which is chromatographed on a column of 9 grams of aluminium oxide (activity Il). With petroleum ether there are obtained from the column 205 mg. of substance melting at 88-90 C; optical rotation [a] =+43 (in chloroform).

Example 4 mg. of A -18 20-cyclo-3fl-acetoxy-allopregnene are ozonized in 10 cc. of ethyl acetate at 70 C. 20 cc. of water and 4 cc. of hydrogen peroxide of 30% strength are added, and the mixture is refluxed for 2% hours. The reaction solution is poured into water and extracted with ether. The ethereal extract is thoroughly washed with water and with slightly acidified ferrous sulfate solution. The resulting product (112 mg. of a colorless oil) is dissolved in 8 cc. of methanolic potassium hydroxide solution of 5% strength and heated for 1 hour at 4550 C. (the oil turns slightly yellowish). After cooling, dilute potassium hydroxide solution is added and the mixture extracted with ether. Working up yields 25 mg. of a neutral product (a colorless oil) and 68 mg. of an acid product (a yellow oil) which is chromatographed on silica gel. A 20:1 mixture of benzene-l-ether elutes 27 mg. of 3fi-hydroxy-ZO-oxo-Sa-pregnane-1S-acid. Infrared spectrum in carbon tetrachloride: 3 440 cm. (hydroxyl band; weak), 1775 cm. (pseudo acid; very strong), 1710 cm? (C-20-ketone band; weak); pK=8.80.

Example 5 A -18%20-cyclo-3B-acetoxy-allopregnene (265 mg), of M.P. 91-91.5 C., optical rotation [a] =+34 (c.=0.740), is purified chromatographically, twice recrystallized, dissolved in 18 cc. of absolute ether and mixed with 220 mg. of osmium tetroxide in 5 cc. of ether. A brown precipitate (osmium'ester) is formed immediately. 0.1 cc. of pyridine is added and the reaction mix tur kept for 2 days in the dark. The solution is evaporated to dryness in vacuo, benzene is added, and the whole is again evaporated. This operation is repeated until the odor of pyridine has disappeared. The residue is dissolved in 30 cc. of absolute benzene and added dropwise to 600 mg. of lithium aluminum hydride in 20 cc. of absolute ether. After completion of the dropwise addition the mixture is refluxed for 5 hours. The lithium aluminum hydride is destroyed with ethyl acetate. The whole is diluted with water, acidified with 2 N-sulfuric acid, and the liquid decanted from the precipitated osmic acid. The hydroxylation product is taken up in ether and washed with 2 N-sulfuric acid and 2 N-potassium carbonate solution.- The resulting pale-yellowish oil (255 mg.)--infrared spectrum in Nujol: strong hydroxyl band at 3350 cm.'- -is filtered through 20 times its own Weight of alumina. The first fraction (225 mg.) is recrystallized from methylene chloride+acetone+hexane, to yield 112 mg. of poorly developed crystals melting at 200-202 C. (Product A), being 18 20-cyclo-3B:18:20-trihydroxyallopregnane. The mother liquor is slightly evaporated in vacuo and kept overnight at C., to yield 60 mg. of fine needles melting at 181 C. (Product B) which, after crystallization from methylene chloride-l-acetone-l-hexane melt at 183 C. Infrared spectrum in Nujol: strong hydroxyl band at 3320 crnr (spectrum is similar to that of the crude product); optical rotation [a] =+l3 (c.=0.776). Product B is an isomeric l.8 20-cyclo-3/3: l8:20i-trihydroxy-allopregnane. The mother liquor is evaporated to dryness in vacuo (Product C).

Example 6 v 109 mg. of 18 20-cyclo-3fl:18zZOE-trihydroxyallopregnane (Product A) are dissolved in 25 cc. of glacial acetic acid and mixed with 162 mg. of lead tetraacetate 1.1 mols) in 6 cc. of glacial acetic acid. 1 cc. chloroform is added and the mixture heated to 40 C. and kept overnight at room temperature. The solution is then heated for 6 hours at 4050 C., poured into ice-Water and extracted with ether. The ethereal layers are washed 12 times with water. The acid constituents are extracted with 3 N-potassium hydroxide solution. Separation produces 86 mg. of a neutral product and 18 mg. of an acid product. Neutral product: infrared spectrum in chloroform: 3600 and 3450 cm.- (hydroxyl band), 1765 cm." and 1723 cmr 60 mg. of the neutral product obtained by oxidation with lead tetraacetate of Product C (Example 5) are chromatographed on 1.2 grams of alumina. 50 cc. of 1:1 petroleum ether+benzene elute 28 mg. of a colorless oil which cannot be oxidized with potassium permanganate;

its elution With ether-{methanol yields 8 mg. of 18*20- cycIo-3 8:18:20g-trihydroxy-allopregnane, identical with Product B (MP. 182 C.).

Acid constituent: The acid constituents from the splitting up with lead tetracetate of Products A and C (Example 5) are combined (31 mg.) and chromatographed over silica gel. lzlbenzene+methylene chloride elutes 25 mg. of 3fl-hydroxy-20-oxo-allopregnane-18-acid; pK 8.70.

Infrared spectrum in Nujol: bands at 1710 and 1735 cmr- Example 7 For the purpose of eliminating water, 1 gram of 18:20- cyclo-A -3ethylenedioxy-ZOg-hydroxy-11 oxopregnene is dis-solved in 200 cc. of absolute xylene, and the boiling solution is mixed with 2.5 grams of fullers earth which has previously been activated by heating for 5 hours in a of 30 grams of alumina, to yield 590 mg. of crystalline 18 20-cyclo-A -3-ethylenedioxy1 l1 oxo pregnadiene; to reduce the carbonyl C-ll it is dissolved as it is in 25 cc. of absolute tetrahydrofuran, and the solution is mixed with 295 mg. of lithium aluminum hydride and refluxed for 3 hours with exclusion of moisture. The excess reducing agent is then destroyed with 1 cc. of ethyl acetate, the mixture is treated with 0.8 cc. of aqueous potassium hydroxide solution, the precipitated aluminum 7 hydroxide is filtered oil and thoroughly rinsed with tetrahydrofuran. The combined filtrates are extensively concentrated at 30 C. in a water-jet vacuum, mixed with water and worked up in the usual manner. To purify the neutral reaction product it is dissolved in 200 cc. of benzene and the solution is filtered through a column of 18 gram-s of alumina. By means of benzene a total of 478 mg. of crystalline l8- 20-cyclo-A 3-ethylenedi oxy-llB-hydroxy-pregnadiene can be isolated which displays in the infrared spectrum a strong absorption band of the free hydroxyl at 3600 cmf but'the carbony band has disappeared.

For conversion into 2l-desoxyaldosterone1 gram of this intermediate product is dissolved in 75 cc. of carbon tetrachloride, 0.5 cc. of pyridine is added, and the solution is treated at 65 to 75 .C. with ozone until 1.2 mols of ozone have been taken up. The above solution is slowly raised to 0 C. the solvent evaporated in a high vacuum, and the residue is dissolved in 20 cc. of glacial acetic acid, treated with 1 gram of freshly activated finely granulated Zinc and then heated for 1 hour at C. To split up the ethylenedioxy grouping, the reaction mixture is treated with 20 cc. of water and heated for another hour at 60 C. Working up yields 810 mg. of neutral ozonisation products which are dissolved in 45 cc. of benzene and chromatographed over a column of 42 grams of alumina. 7:1 and 5:1 mixtures of benzene-l-ether elute from the column a total of 385 mg. of crystals which display in the ultraviolet absorption spectrum in absolute alcohol the band typical of cup-unsaturated ketones at 240 m log c=4.21. The infrared spectrum contains the following bands: 3520 cm.- (hydroxyl of the serniacetal grouping); 1720 cm." (carbonyl C-20); 1683 cmr 1635 cm." (MB-unsaturated Oarbonyl grouping of ring A).

The resulting product reduces silver diamine and Fehlings solution; it is the 2l-desoxyaldosterone of the formula By oxidation with chromic acid+pyridine it can be oxidized to the corresponding 18 11-lactone of the formula Example 8 and (2) 305 mg. of the ester -o-i i-o--- melting at 191-1915 C. (from methylene-chloride-hexane); infrared spectrum: no hydroxyl or carbonyl bands.

C45H55O7SZ CalculatedC, 72.42%; H, 8.72%; S, 4.20% F0und-C, 72.47%; H, 8.71%; S, 4.33%

By treating this sulfite ester with sodium methylate of strength of an water bath and purifying the crude product by chromatography, A -3-ethylenedioxy-2OIg-hydroxy-18:20-cyclo-pregnene is obtained; yield=80%.

Example 9 For the purpose of eliminating water 1 gram of A -3- ethylene dioxy 20$ hydroxy 21 acetoxy-18:20-cyclopregnene is dissolved in 50 cc. of absolute ether, 2 cc. of phosphorus oxychloride and 4 cc. of pyridine are cautiously added to the solution at 15 C. and the whole allowed to stand for 5 hours at 0 C. After working up in the usual manner, 950 mg. of an amorphous, halogen-free crude product are obtained which is chromatographed on a column of 45-grams of aluminum oxide (activity II). The column is eluted with mixtures of petroleum ether and benzene 1:1 to 1:5 and a total of 520 mg. of crystalline A -3-ethylenedioxy-21-acetoxy-18 :20-cyclo-pregnadiene is obtained which is dissolved without further purification in 50 cc. of absolute carbon tetrachloride for the purpose of ozonization, and, after adding 1 cc. of pyridine at 70 C., the solution is treated with ozone until about 1.1 mols of ozone have been taken up. The oily solution is then slowly heated to +5 C., the solvent cautiously evaporated under reduced pressure, the residue dissolved in 15 cc. of glacial acetic acid, 500 mg. of freshly activated zinc grit are added to the solution and the whole is heated for one hour on a water bath. In order to split the ethylenedioxy grouping 8 cc. of water are added to the reaction mixture and the whole allowed to stand for another hour at 60 C.

After working up, there are obtained 318 mg. of neutral ozonization product which is purified by chromatography on a column of 30 grams of silica gel. The A 3:18:20-trioxo-2l-acetoxy-pregnene obtained in this manner exhibits in the ultraviolet spectrum the typical bands of the cup-unsaturated ketone grouping of ring A (242 mu, log 5:4.17 in rectified spirit). In the infrared spectrum (chloroform) there are the following bands: 2720 cm.- (aldehyde C-18), 1745-1710 cm.- (acetate radical 21 and carbonyl groups C-18 and C-20) and a doublet 1683/1620 cm.- (A -3-ketone).

Example 10 A 3-ethylenedioxy-2l-acetoxy-l1-keto-18z20-cyclopregnadiene are eluted from the column and dissolved without further purification in cc. of absolute methanol and reduced at the boil with 200 mg. of sodium boron hydride. After working up and purifying by chromatography on a column of 50 grams of silica gel, crystalline A 3 ethylenedioxy-llfi-hydroxy-Zl-acetoxy- 18:20-cyclo-pregnadiene (625 mg.) is obtained.

This intermediate product can be converted into aldosterone-Zl-acetate in the following manner: 1 gram of substance dissolved in 100 cc. of absolute carbon tetrachloride and 1 cc. of absolute pyridine is ozonized at -75 C. until 1.2 mols of ozone have been taken up. The solvent is then cautiously evaporated at 0 C. under reduced pressure, the amorphous ozonide dissolved in 20 cc. of ethyl acetate and, after adding 1 gram of a palladium-calcium carbonate catalyst of 5% strength, split by reduction. There is obtained A -3-ethylenedioxy-1lp-hydroxy-2l-acetoxy-18:20-dioxo-pregnene which, after being heated for a short time at 80 C. with acetic acid of 90% strength, is split to form aldosterone-ZI-acetate.

Example 11 For the purpose of eliminating water, A -3-ethylenedioxy 20g hydroXy-llfi-acetoxy-l8:20-cyclo-pregnenc is treated at a low temperature with phosphorus oxychloride and pyridine and the resulting A -3-ethylenedioxyllfl-a'cetoxy 18:20-cyclo-pregnadiene reduced with lithium aluminum hydride in absolute tetrahydrofuran. After these operations A -3-ethylenedioxy-1lfl-hydroxy- 18:20-cyclo-pregnadiene described in Example 7 is obtained.

What is claimed is:

1. The A -18:20-cyclo-3 fl-acetoxy-allopregnene.

2. The M 18:20-cyclo-3-ethylenedioxy-pregnadiene.

3. The A 18:20 cyclo-3-ethylenedioxy-1l-oxopregnadiene.

4. The A 18:20 cyclo 3-ethylenedioxy-11fi-hydroxy-pregnadiene.

5. The A 18:20- cyelo-3-ethylenedioxy-1lfl-acetoxy-pregnadiene.

6. The A 18:20- cyclo-3-ethylenedioxy-1lp-hydroxy-2I-acetoxy-pregnadiene.

7. The A -18:20 cyclo-3-ethylenedioxy-11-oxo-2lacetoxy-pregnadiene.

8. The A -18:20-cyclo-3-ethylenedioxy-2l-acetoxypregnadiene.

9. The 18:20-cyclo-3/3,18,ZO-trihydroxy-allogpregnane.

10. The 3/9-acetoxy-18:20-dioxo-allopregnane.

11. The 3p8-acetoxy-ZO-oxo-allopregnane-1S-acid.

12. The 3fl-hydroxy-20-oxo-allopregnane-l8-acid.

13. Process for the manufacture of A -pregnene compounds, which comprises dehydrating a member selected from the group consisting of an 18:20-cyclo-20- hydroxy-pregnane unsubstituted in the 18- and 21-positions, and a derivative thereof unsaturated in the nucleus, by means of a member selected from the group consisting of a halide of sulfurous acid, phosphoric acid and of an organic sulfonic acid in the presence of a tertiary organic nitrogen base.

14. Process for the manufacture of d -pregnene compounds, which comprises dehydrating a member selected from the group consisting of an 18:20-cyclo-20- hydroxy-pregnane unsubstituted in the 18- and 21-positions, and a derivative thereof unsaturated in the nucleus, by heating with a member selected from the group consisting of an anhydride of an organic carboxylic acid, and a mixture thereof with such an acid.

15. Process for the manufacture of A -pregnene compounds, which comprises esterifying a member selected from the group consisting of an 18:20-cyclo-20- hydroxy-pregnane, and a derivative thereof unsaturated in the nucleus, with a member selected from the group consisting of an acid anhydride and an acid chloride in the presence of a tertiary organic base, and splitting the resulting 20-O-acy1 derivative by heating to form an 18 :20-cyclo-A -pregnene derivative.

16. Process for the manufacture of A -pregnene compounds, which comprises dehydrating a member selected from the group consisting of an 18:20-cyclo-20- hydroxy-pregnane unsubstituted in the 18- and 21-positions, and a derivative thereof unsaturated in the nucleus, by treatment'with fullers earth.

17. Process for the manufacture of Iii-oxygenated pregnane compounds, which comprises treating a member selected from the group consisting of a Aff pregnane which is unsubstituted in the 18- and 21-positions, and a derivative thereof unsaturated in the nucleus, with ozone and splitting the resulting ozonide by means of a reducing agent.

18. Process for the manufacture of 1 8-oxygenated pregnane compounds, which comprises treating a member selected from the group consisting of a A -pregnane which is unsubstituted in the 18- and ZI-positions, and a derivative thereof unsaturated in the nucleus, with osmium tetroxide, then treating the resulting product with a member selected from the group consisting of lead tetraacetate, per-iodic acid and sodium bismuthate.

19. A member selected from the group consisting of 11 -18:20-cyclo-pregnenes having the formula CHi-Rn CH=C and the corresponding compounds which contain a double bond starting from carbon atom 5, in which formula R stands for a member of the group consisting of x0 and ethylenedioxy, R for a member of the group consisting of hydrogen, oxo, hydrogen together with lower acyloxy and R for a member of the group consisting of hydrogen, hydroxyl and lower acyloxy.

20. A member selected from the group consisting of 18:20-dihydroxy-18z20-cyclo-pregnanes having the formula and the corresponding compounds which contain a double bond starting from carbon atom 5, in which formula R stands for a member of the group consisting of 0x0 and ethylenedioxy, R for a member of the group consisting of hydrogen, oxo, hydrogen together with hydroxy and hydrogen together with lower 'acyloxy and R for a member of the group consisting of hydrogen, hydroxyl and lower acyloxy. I

21. Process for the manufacture of A -pregnene compounds, which comprises dehydrating wherein a member selected from the group consisting of an 18:20-cyclo- ZO-hydroxy-pregnane unsubstituted in :the 18- and 21-positions, and a derivative thereof unsaturated in the nucleus, by means of a member selected from the group consisting of bromacetamide and bromsuccinimide in pyridine, then 1 treating the resulting product with sulfur dioxide.

22. Process for the manufacture of A -pregnene compounds, which comprises dehydrating a ZO-sulfonic acid ester of a member selected from the group consisting of an 18:20-cyclo-20-hydroxy pregnane, and a deriva- I tive thereof unsaturated in the nucleus, by means of lithium chloride in dimethyl formamide.

23. Process for the manufacture of l8-oxygenated References Cited in the file of this patent UNITED STATES PATENTS Wettstein et al. Jan. 22, 1957 Ruzicka et a1 Jan. 13, 1959 UNITED STATES- PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,014,029 December 19, 1961 Oskar Jeger It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as oorreoted below.

Column 9, lines 26 to 35, the formula should appear as shown below instead of as in the patent:

column 10, lines 1 to 10, the formula should appear as shown below instead of as in the patent:

3 OH F11 R CHC-OH same column 10, line 20, strike out "'wherein'fl.

I Signed and sealed this 4th day of September 1962.

(seam Attesti ERNEST W0 SWIDER DAVID L, LADD Atte'sting Officer Commissioner of Patents 

2. THE $5:18:20-18:20-CYCLO-3-ETHYLENEDIOXY-PREGNADIENE.
 13. PROCESS FOR THE MANUFACTURE OF $18:20-PREGNENE COMPOUNDS, WHICH COMPRISES DEHYDRATING A MEMBER SELECTED FROM THE GROUP CONSISTING OF AN 18:20-CYCLO-20HYDROXY-PREGNANE UNSUBSTITUTED IN THE 18- AND 21-POSITIONS, AND A DERIVATIVE THEREOF UNSATURATED IN THE NUCLEUS, BY MEANS OF A MEMBER SELECTED FROM THE GROUP CONSISTING OF A HALIDE OF SULFUROUS ACID, PHOSPHORIC ACID AND OF AN ORGANIC SULFONIC ACID IN THE PRESENCE OF A TERTIARY ORGANIC NITROGEN BASE. 